求解OG一道数学题，Data Analysis Exercieses ?

hom0913UID: 3023725

哪位大侠能给我解释下第二问？
5. Eight hundred insects were weighed, and the resulting measurements, in milligrams, are summarized in the boxplot below.


(a) What are the range, the three quartiles, and the interquartile range of the measurements?
(b) If the 80th percentile of the measurements is 130 milligrams, about how many measurements are between 126 milligrams and 130 milligrams?


不知道怎么贴图？
有谁能告诉我？

hom0913UID: 3023725

自己顶下~~

gracesrmUID: 3185356

我看了答案以后觉得吧，应该是说130那个地方是80%，然后根据Q3（126）处应该是75%，所以二者之间是5%， 800*5%=40了！

乐百氏开开心心UID: 3459533

gracesrm 发表于 2011-11-9 18:48
我看了答案以后觉得吧，应该是说130那个地方是80%，然后根据Q3（126）处应该是75%，所以二者之间是5%， 800 ...

为什么126的地方是75%呢？怎么算的呢？